Alert archive / Illinois / Mesoscale Discussions in 2020
Mesoscale Discussion 620
The Storm Prediction Center issued this mesoscale discussion at May 17, 2020, 1:44 PM CDT for 51 counties in Illinois; 20 counties in Indiana. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- May 17, 2020, 1:44 PM CDT (18:44 UTC)
- Expired
- May 17, 2020, 3:45 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch possible
- Chance of a watch
- 60%
All 71 counties
Bond County, IL, Champaign County, IL, Christian County, IL, Clark County, IL, Clay County, IL, Clinton County, IL, Coles County, IL, Crawford County, IL, Cumberland County, IL, DeKalb County, IL, DeWitt County, IL, Douglas County, IL, DuPage County, IL, Edgar County, IL, Edwards County, IL, Effingham County, IL, Fayette County, IL, Ford County, IL, Franklin County, IL, Gallatin County, IL, Grundy County, IL, Hamilton County, IL, Iroquois County, IL, Jasper County, IL, Jefferson County, IL, Kankakee County, IL, Kendall County, IL, LaSalle County, IL, Lawrence County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Madison County, IL, Marion County, IL, McLean County, IL, Montgomery County, IL, Moultrie County, IL, Perry County, IL, Piatt County, IL, Richland County, IL, Saint Clair County, IL, Saline County, IL, Sangamon County, IL, Shelby County, IL, Vermilion County, IL, Wabash County, IL, Washington County, IL, Wayne County, IL, White County, IL, Will County, IL, Woodford County, IL, Benton County, IN, Clay County, IN, Fountain County, IN, Gibson County, IN, Jasper County, IN, Knox County, IN, Lake County, IN, Montgomery County, IN, Newton County, IN, Parke County, IN, Porter County, IN, Posey County, IN, Pulaski County, IN, Putnam County, IN, Sullivan County, IN, Tippecanoe County, IN, Vermillion County, IN, Vigo County, IN, Warren County, IN, White County, IN
The radar
The Lincoln radar (KILX), 86 km from the middle of the area, began a volume at 18:46 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Lincoln, IL (KILX), launched 12:00Z, 6.7 hours before the alert went out and 31 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 40 J/kg
- Mixed-layer CIN
- -26 J/kg
- Mixed-layer LCL
- 599 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 167 m²/s²
- 0-3 km storm-relative helicity
- 173 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 17, 4:18 PM CDT | Severe Thunderstorm Watch | SPC | Champaign, Clark, Clay, Coles, Crawford, Cumberland and 25 more | 5 hr |
| May 17, 6:29 PM CDT | Mesoscale Discussion | SPC | Gallatin, Lawrence, Wabash | 91 min |
Nearby
Mesoscale Discussions in Illinois, 2020Mesoscale Discussions in Indiana, 2020Every mesoscale discussion in 2020
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.